Peggy Shannon, 67, who works part-time at the Senior Citizens Service Desk in the lobby of the City Administration Building, said Thursday that Filner repeatedly asked her out during work and that he once grabbed her and kissed her on the lips.

Shannon claims that Filner, 70, also once told her that he could 'go eight hours straight' in an apparent reference to sex.

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Peggy Shannon (left) claimed in a press conference with attorney Gloria Allred (right) that Mayor Bob Filner kissed her and made inappropriate comments to her

Peggy Shannon, 67, a volunteer city worker who assists senior citizens, is the latest person to accuse Filner of sexual harassment

Peggy Shannon who works at the Senior Citizens Service Desk in San Diego City Hall

San Diego Mayor Bob Filner speaks during a news conference at city hall on July 26, 2013. Filner is challenging a recall effort after more than a dozen women have accused him of sexual harassment

Michelle Tyler alleges San Diego Mayor Bob
Filner made inappropriate advances on her while she was seeking help for
Marine Katherine Ragazzino (right)

Earlier Thursday, attorney Kathryn Vaughn became the 15th woman to come forward with sexual harassment accusations against the mayor.

Vaughn said she encountered Filner 10 years ago at a public event when he was a congressman.

'He made an inappropriate movement on my body, yes,' Vaughn said when asked if she was groped.

University of California, San Diego, political science professor Steve Erie said Filner seems to be in denial but also may be trying to appear like he is digging in his heels so he has more negotiating power over his future.

The mayor's stubbornness could be aimed at leveraging a deal to leave office under the condition that he shed his financial responsibilities if the city loses a sexual harassment lawsuit filed by Filner's former communications director, Irene McCormack Jackson, Erie said.

'I think what we're seeing here is bunker mentality,' Erie said. 'I think our mayor is still in denial or he wants to appear like he will resolve to fight it to the end. This may be a bargaining strategy, because the minute he resigns, all bets are off, and he's lost leverage.'

Several businesses — including four Hooters restaurant locations — have posted signs from a radio talk show campaign stating the establishments will not serve the mayor because 'we believe women should be treated with respect.'

Melissa Fry, director of marketing for HootWinc, the West Coast Hooters franchise told Slate magazine it was not a political move but was a stand for the fair treatment of women.

Action: Irene McCormack Jackson, the mayor's former director of communications Jackson sued the mayor and the city on July 22

Filner has not been seen publicly since entering an intensive two-week therapy session. His lawyers said Filner would not be available for comment this week while he receives outpatient care.

The mayor has apologized for what he says was inappropriate behavior and acknowledged disrespecting and intimidating women. But he has said he is not guilty of sexual harassment.

The nine-member City Council and state and federal elected officials have urged Filner to step down.